The International Space Station or ISS for short is the result of nations working together to further their knowledge of space. Unlike the previous attempts by the Russians and the Americans (N.A.S.A), this one is truly collaborative. In the past, the Americans built and put Skylab in the 1970's and the Russians had Mir which means Peace in the 1980s. It is the largest man-made object in space and can be seen with a naked eye if you know where to look. Its position can be tracked on the E.S.A. website, there's probably an equivalent page on NASA or on the Russian Space Agency site.
If you think it is anything like the space stations you've seen such as Babylon 5 or the dreaded Death star, you will be heavily disappointed. For a start, neither of the space station have their own gravity. For that astronauts need to exercise vigorously for two hours a day otherwise their muscles will waste away due to their being in zero gravity. Whilst it might sound like fun being in zero gravity, it will eventually get boring as you won't be able to switch on gravity. If you ever watch videos of life onboard the space station, you will see astronauts floating aboat, never walking.
It was put into space part at a time, rather than all in one go. Different components were made by different countries but predominantly by United States and Russia. The first part was launched by rocket but then after that, the Space Shuttle was used to ferry the parts to be connected on until the fleet was retired. The first part was the 'Zarya' Control Module followed shortly by the 'Unity' module that was taken up by the space shuttle Endeavour. The complete time line can be found at the ESA ISS webpage. At the time of writing this page, August 2014, it was not fully finished, another module, a multi-purpose Laboratory Module was due to be attached to the craft in 2015.
The following video that was uploaded to Youtube shows you around the International Space Station and you can see how relatively spacious it can be.
If you'd like to see the interior of the ISS with background music, you can watch Canadian Astronaut Chris Hadfield's rendition of David Bowie's Space Oddity. The video shows sights of inside, outside and looking down on the Earth below. If you Youtube Chris, you will also see videos he's made to explain and answer questions that have been posed to him such as what happens when you cry in space.
Whilst in the early days, the Americans would be transported to the ISS onboard the Space Shuttle, now they don't have that luxury, instead they are transported aboard by the Russians from their port in Kazakhstan in Soyuz space crafts. There is a Soyuz space craft permanently attached to the ISS in case the crew need to evacuate the craft at a moments notice.
The memorandum of understanding of the International Space Station lasts until 2020 when a new one will probably be drawn up between the United States and Russia primarily allowing them to continue.
Every so often, they will receive supplies from Earth, there will never be home comforts that we are used to on Earth. Water is sachets which must be kept closed when not drinking otherwise water will float out of the bags. Sleeping is done in sleeping bags and you can find yourself standing up for a lot of the time.
As part of the Royal Institute Lectures of 2015, British Astronaut Tim Peake was asked what it smelled like onboard the space station, he responded that the smell was metallic but not in a bad way but "chemically".